o positions
the one near the Fair Grounds seems the more likely (fig. 1), for at
this place the river has excavated a recent channel with steep sides
in gneissoid rock. The absence of the limestone at this point may be
sufficient in itself to explain the location of the divide.

Exact measurements of the drift in the upper Still valley are needed
in order to establish this hypothesis completely and to plot the old
channel, but the position of the rock floor of the former channel
extending westward from the Fair Grounds may be fixed approximately.
The rock at the assumed divide now stands at 420 feet above sea-level
and it is reasonable to assume that ten feet has been removed by
glacial scouring and postglacial erosion, making the original
elevation 430 feet. The present divide between Andrew Pond and Haines'
Pond has an elevation of 460, but the bedrock at this place is buried
under 60 feet of drift, so that the valley floor lies at 400 feet.
According to these estimates the stream which headed east of the Fair
Grounds had a fall of 30 feet before reaching the site of the present
Haines' Pond (fig. 8, B).

GLACIAL LAKE KANOSHA

When the Croton Branch was beheaded by drift choking up its valley
west of Andrew Pond, the ponded waters rose to a height of from 20 to
30 feet and then overflowed the basin on the side toward Danbury. The
outlet was established across the old divide, and as the gorge by
which the water escaped was cut down, the level of the ponded waters
was lowered. At the same time, also, the lake was filled by debris
washed into it from the surrounding slopes. Thus the present flat
plain was formed and the old valley floor, a local peneplain developed
on the limestone, was hidden.

DIVIDES IN THE HIGHLANDS SOUTH OF DANBURY

The mountain mass to the south and southwest of Danbury, including
Town Hill and Spruce, Moses, and Thomas mountains, is traversed by a
series of parallel gorges trending nearly north and south (fig. 2).
About midway in each valley is a col, separating north and
south-flowing streams. Two of the valleys, those between Spruce and
Moses mountains, and Thomas Mountain and Town Hill, form fairly low
and broad passes. They were examined to see whether either could have
afforded a southerly outlet for Still River.

The rock composing the mountains is granite-gneiss and schist with an
average strike of N 30 deg. W, or very nearly in line with the trend of
the valleys. The gneiss was